Generation of output is now done through a stream iterator instead of the stream directly, which improves performance. Also made more compact generator for xml header, root element and bgcolor.

src/svg/process_building_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(building_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(building_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_glyph_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(glyph_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(glyph_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_line_pattern_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(line_pattern_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(line_pattern_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_line_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(line_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(line_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_markers_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(markers_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(markers_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_point_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(point_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(point_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_polygon_pattern_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(polygon_pattern_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(polygon_pattern_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_polygon_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(polygon_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(polygon_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_raster_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(raster_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(raster_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_shield_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(shield_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(shield_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/process_text_symbolizer.cpp

@@ -34,7 +34,7 @@ namespace mapnik
 	// nothing yet.
     }
 
-    template void svg_renderer<std::stringstream>::process(text_symbolizer const& sym,
-							   Feature const& feature,
-							   proj_transform const& prj_trans);
+    template void svg_renderer<std::ostringstream>::process(text_symbolizer const& sym,
+							    Feature const& feature,
+							    proj_transform const& prj_trans);
 }

src/svg/svg_renderer.cpp

@@ -29,6 +29,10 @@
 #include <iostream>
 #endif
 #include <sstream>
+#include <fstream>
+
+// boost
+#include <boost/fusion/tuple.hpp>
 
 // boost.spirit
 #include <boost/spirit/include/karma.hpp>
@@ -36,7 +40,7 @@
 
 namespace karma = boost::spirit::karma;
 namespace repository = boost::spirit::repository;
-namespace ascii = karma::ascii;
+namespace fusion = boost::fusion;
 
 namespace mapnik
 {
@@ -79,55 +83,49 @@ namespace mapnik
 	std::clog << "start map processing" << std::endl;
 	#endif
 
-	using repository::confix;
-	using karma::format;
-	using karma::lit;
-	using karma::eol;
-	using karma::int_;
-	using karma::double_;
-	using ascii::string;
-	using ascii::space;
-
 	// should I move these lines to the constructor?
+	// agg_renderer processes the background color of the map in the constructor.
+
+	using namespace karma;
+	using karma::string;
+	using repository::confix;
+	using fusion::tuple;
+
+	std::ostream_iterator<char> output_stream_iterator(output_stream_);
 
 	// generate XML header.
-	output_stream_ << format(string << eol << string << eol, XML_DECLARATION, SVG_DTD);
+	generate(
+	    output_stream_iterator,
+	    string << eol << string << eol, 
+	    XML_DECLARATION, SVG_DTD);
 
 	// generate SVG root element opening tag.
-	output_stream_
-	    << format(
-		confix("<svg width=\"", "\"")[int_ << string],
-		width_, "px")
-	    << format(
-		confix(" height=\"", "\"")[int_ << string],
-		height_, "px")
-	    << format(
-		confix(" version=\"", "\"")[double_],
-		SVG_VERSION)
-	    << format(
-		confix(" xmlns=\"", "\">")[string],
-		SVG_NAMESPACE_URL);
+	// the root element defines the size of the image,
+	// which is taken from the map's dimensions.
+
+	generate(
+	    output_stream_iterator,
+	    confix("<", ">")[
+		"svg width=" << confix('"', '"')[int_ << string]
+		<< " height=" << confix('"', '"')[int_ << string]
+		<< " version=" << confix('"', '"')[float_]
+		<< " xmlns=" << confix('"', '"')[string]]
+	    << eol,
+	    tuple<int, std::string>(width_, "px"), tuple<int, std::string>(height_, "px"), SVG_VERSION, SVG_NAMESPACE_URL);
 
 	boost::optional<color> const& bgcolor = map.background();
 	if(bgcolor)
 	{
 	    // generate background color as a rectangle that spans the whole image.
-	    output_stream_
-		<< format(
-		    confix("\n<rect x=\"", "\"")[int_],
-		    0)
-		<< format(
-		    confix(" y=\"", "\"")[int_],
-		    0)
-		<< format(
-		    confix(" width=\"", "\"")[int_ << string],
-		    width_, "px")
-		<< format(
-		    confix(" height=\"", "\"")[int_ << string],
-		    height_, "px")
-		<< format(
-		    confix(" style=\"fill: ", "\"/>")[string],
-		    bgcolor->to_hex_string());
+	    generate(
+		output_stream_iterator,
+		confix("<", "/>")[
+		    "rect x=" << confix('"', '"')[int_]
+		    << " y=" << confix('"', '"')[int_]
+		    << " width=" << confix('"', '"')[int_ << string]
+		    << " height=" << confix('"', '"')[int_ << string]
+		    << " style=" << confix('"', '"')["fill: " << string]],
+		0, 0, tuple<int, std::string>(width_, "px"), tuple<int, std::string>(height_, "px"), bgcolor->to_hex_string());
 	}
     }
 
@@ -138,7 +136,6 @@ namespace mapnik
 	using karma::lit;
 
 	// generate SVG root element closing tag.
-	// this doesn't work.
 	output_stream_ << format(lit("\n</svg>"));
 
 	#ifdef MAPNIK_DEBUG
@@ -166,5 +163,6 @@ namespace mapnik
 	#endif
     }
 
-    template class svg_renderer<std::stringstream>;
+    template class svg_renderer<std::ostringstream>;
+    template class svg_renderer<std::ofstream>;
 }

tests/cpp_tests/svg_renderer_tests/background_color_test.cpp

@@ -133,3 +133,33 @@ BOOST_FIXTURE_TEST_CASE(bgcolor_stream_confix_complete_test_case, F)
     
     BOOST_CHECK_EQUAL(actual_output.str(), expected_output);
 }
+
+/*
+ * This test case uses an iterator to receive the generated
+ * output. The iterator comes from the std::ostringstream that's
+ * been used in the previous test cases, so the output is
+ * actually generated into the stream.
+ *
+ * Using iterators instead of streams has the advantage that
+ * more advanced concepts are implemented in karma for them,
+ * like rules and grammars.
+ */
+BOOST_FIXTURE_TEST_CASE(bgcolor_stream_iterator_test_case, F)
+{
+    using repository::confix;
+    using fusion::tuple;
+
+    std::ostream_iterator<char> actual_output_iterator(actual_output);
+
+    generate(
+	actual_output_iterator,
+	confix("<", "/>")[
+	    "rect x=" << confix('"', '"')[int_]
+	    << " y=" << confix('"', '"')[int_]
+	    << " width=" << confix('"', '"')[int_ << string]
+	    << " height=" << confix('"', '"')[int_ << string]
+	    << " style=" << confix('"', '"')["fill: " << string]],
+	x, y, tuple<int, std::string>(width, "px"), tuple<int, std::string>(height, "px"), bgcolor);
+
+    BOOST_CHECK_EQUAL(actual_output.str(), expected_output);
+}

tests/cpp_tests/svg_renderer_tests/combined_test.cpp

@@ -26,12 +26,12 @@
 BOOST_AUTO_TEST_CASE(combined_test_case)
 {
     using namespace mapnik;
-    typedef svg_renderer<std::stringstream> svg_ren;
+    typedef svg_renderer<std::ostringstream> svg_ren;
 
     Map map(800, 600);
     map.set_background(color_factory::from_string("white"));
 
-    std::stringstream output_stream;
+    std::ostringstream output_stream;
     svg_ren renderer(map, output_stream);
     renderer.apply();
 

tests/cpp_tests/svg_renderer_tests/compilation_test.cpp

@@ -1,4 +1,4 @@
-#define BOOST_TEST_MODULE compile_tests
+#define BOOST_TEST_MODULE compile_test
 
 // boost.test
 #include <boost/test/included/unit_test.hpp>
@@ -23,13 +23,12 @@ BOOST_AUTO_TEST_CASE(compile_test_case)
 
     try
     {
-        std::stringstream output_stream;
-        svg_renderer<std::stringstream> renderer(map, output_stream);
-        renderer.apply();
-        std::clog << output_stream.str() << "\n";
+	std::ostringstream output_stream;
+	svg_renderer<std::ostringstream> renderer(map, output_stream);
+	renderer.apply();
     }
     catch(...)
     {
-        BOOST_FAIL("Empty implementation throws exception.");
+	BOOST_FAIL("Empty implementation throws exception.");
     }
 }